The robot junkies over at Automaton inform us of a new robotic milestone (or whatever the nautical equivalent of a milestone is, perhaps a “milebuoy”). Four self-propelled robots recently set sail from San Francisco on a 37,000-mile journey across the Pacific Ocean. If the swimming bots manage to weather all the storms, dodge all the ships, and not get devoured by any sharks (admittedly unlikely), then they’ll set a new Guinness record for the longest unmanned sea voyage.

The four robots, which are about the size of a dolphin, according to Automaton, will be headed for Hawaii, at which point they’ll divide into pairs, with one couple headed for a Japan, another for Australia. The main purpose of the journey appears to be scientific. The bots will be collecting all sorts of data (via solar-powered sensors): salinity, water temperature, oxygen content, as well as information on waves and currents. All the data will be streamed via satellite and made available to anyone for free via Google Earth’s Ocean Showcase. Liquid Robotics will in fact give a prize for proposals for the best use of its data. (You can register for access to the data here.)

The Wave Gliders (which run about $200,000) have been on the market since 2008, and have logged a collective 100,000 miles of operations, according to Liquid Robotics. How exactly do they work? They have a two-part architecture: a float that scoots along the surface, connected by a cable to a finned glider beneath the surface. This setup allows the devices to convert wave motion into thrust. “This means that Wave Gliders can travel to a distant area, collect data, and return for maintenance without ever requiring a ship to leave port” to refuel or collect the devices, says Liquid Robotics on its site.

The idea of a swimming robot, of course, is not new. There have been biomimetic designs like this robotic manta ray, and the U.S. Navy’s use of unmanned undersea vehicles dates back to the Cold War era at this point. Here’s a swimming robot that relies on a fin that runs the length of its body.

If any of those robots once held the Guinness title for longest unmanned sea voyage, they’d better be prepared to give it up. Thankfully researchers have not yet programmed swimming robots capable of feeling a gut-wrenching sense of loss.